Sound amplifier



J. B. HAWLEY SOUND AMPLIFIER Sept. 3, 1929.

Filed Sept. 27, 1924 2 Sheets-Sheet 1 Inl/eraf@ 7^.' 755e ffm/J Sept. 3,1929. J, B, HAWLEY 1,727,105

SOUND AMPLIFIER Filed Sepp. 27, 1924 2 sheets-sheet. 2

Patented Sept. 3, 1929.

UNITED STATES PATENT OFFICE.

JESSE 1B. HAWLEY, OF WILMETTE. ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO UNITED REPRODUCERS CORPORATION, F ST. CHARLES, ILLINOIS, A COR-PORATION 0F NEW JERSEY.

SOUND AMPLIFIER.

Application filed September 27, 1924. Serial No. 740,160.

The present invention relates to sound amplifiers, such as those used intalking machines, radio apparatus and like and similar devices.

Among the objects of the invention are to provide a novel device foramplifying sound free from distortion, and discordant tones, andincorrect timbre, metallic resonance, and the like but which willproduce sound or sound waves as nearly true to theoriginal or createdsound as possible; to provide for reflecting the emitted reproducedsound waves for purifying the sounds and timbre; to successively reflectsuch waves; to provide for adjusting the relation of the reflectors withrespect to each other; to provide a reflector .with a substantiallycausticl surface for efficiently reflecting a sound conducted to it fromthe reproducer; to provide a reflector of hollow form and of'substantially frusto-conical forms or portions with reflecting surfacesand passage defining walls; to provide a pair of reflectors having theirreflecting portions directed toward each other suoli that the soundincident upon one may be reflected to the other and the latter toreflect the sound by the former and to the exterior of the device, theformer reflector being spaced from the other reflector to provide achannel or passage therebetween; to provide for adjusting the spacebetween such reflectors' for varying the quality and volume of thesound; to provide one of the reflectors witha projection preferablyextending into the discharge end of the sound conveying passage or tubeto aid in directing the sound into the reflecting passages; to provide asimple and convenient means for supporting the reflector in position foradjustment to and from the sound conveying tube and the other reflectingportion of the def vice; and to provide such other objects, advantagesand capabilities as Will later appear and are inherently possessed bythe' 1nvention.

In the drawing showingan illustrative embodiment of the invention, Fig.1 is a perspective view of an amplifier constructed in accordance withthe invention; Fig. 2 1s a 60 transverse sectional view through thesame, Fig. 3'is a front view in elevation, partly broken away, of thedevice; Fig. 4 is a sectional view of a modified form of my' horn; Fig.5 is a section on line 5 5 of Fig. '4;

screw; and Fig. 8 is another view of the block shown in Fig. G.

Referring more particularly to the drawing, one form of deviceconstructed in accordance with the invention is shown an amplifiercomprising a central sound conveying tube 1 preferably diverging towardthe forward end 2 thereof and provided at the rear end portion 3 thereofwith means for the attachment thereto of a sound reproducer, receiver orthe like 4, having a sleeve 5 adapted to be connected with the end 3 ofthe tube. The forward end of the tube 1 extends and curves laterally toform a connecting portion (i which extends into a flaring truste-conicalwall or portion 7 flaring toward the rear and arranged substantially inconcentric relation` withfthe tube 1, as clearly shown in Fig. 2 of thedrawing. The rear end portion 8 of this part extends and curveslaterally into a forwardly extending Haring or substantiallyfrusto-conical body portion 9 which is also substantially concentricwith the portion 7 and the tube 1, and presenting a mouth 10 at theforward side of the device through which the sound is finally emittedinto the atmosphere.

Opposite the open end 2 of the tube is located a reflector 11 having acaustic surface 12 providing a projecting portion 13 extending more orless into the open end portion of the tube 1, as, clearly shown in Fig.2. The reflector 11 has a-rearwardly extending` substantially annularportion or wall 14 preferably in the form of a frustocone andsubstantially parallel to the wall of the member 7 and spaced therefromso as to provide a diver-ging passage 15 between the walls 7 and 12whereby the sound may travel rearwardly toward the reflecting portion 8between the walls 7 and 9 of the device.

The reflector 11 is preferably mounted for adjustment so that the spacebetweenthe reflector and the open end of the tube 2 and the wall 7 maybe varied as desired. For the purpose of adjustably mounting thisreflector, the body portion 9 has a supporting element 16 clasping therim 17 of the device and extending in the form of a band or bar acrossthe mouth 10 and provided with a threaded hub 18 in which is threaded ascrew 19 provided with a thumb nut 20 at the outer end thereof andpivotally connected .at the other end thereof with a plate 21 secured,in any suitable manner, to the forward end of the reflector 6, as clealyshown in Figi 2 of the drawing. It will be apparent from the above thatby turning the thumb nut 20 the screw may be operated to move thereflector 11 longitudinally to and from the open end of the tube 1 andthe wall portion 7 so as to vary the space therebetween.

The tube and reflecting portions of the devvice may be made of anysuitable material,

such as of wood, metal, papier mch, or interlaced fibers, made inaccordance with my process Serial No. 620,579, filed' February 23, 1923.

Figs. 4 to 8 disclose a modified horn construction'wherein the horn bodyportion 9 is formed with the central sound conveying tube 1 except thatthis tube is formed with a channel or seat on its inner periphery intowhich seat -is fitted a block formed with a central, threaded bore 23and radial wings 24 which are formed with rather sharp knife-like edges25 and .stream-line shaped sides. The central Vsubstantially cylindricalhub 27 of theblock'is also provided with a Slight concave curvature.28to present less independence to the passage of the sound waves from thevibrating diaphragm located in the housing 4. The reflector 11 isprovided at its central portion with an adjusting screw 29 rigidlyattached thereto as at 30. The threaded portion of the screw engages thethreads on the inner bore 23 of the block so that `when the screwis.turned the reflector will the tube 1 where it is transmittedlongitudinally thereof toward the reflector 11 and permitted to expandby reason of the flaring of the tube. The sound will then act againstthe caustic surface of the reflectorl and pass into the annular assagebetween thewalls 7 and 14 after it is reflected from the inner surfaceof the reflector 11 and be transmitted toward the rear partly Vagainstthe outer ,surface of the wall 7 and a curved ortion 8 between the walls7 and 9 anden projected from the inner surface of the wall 9 andtransmitted to the atmosphere through the mouth 10. When it is desiredVto v ary thequality of the tones and the volume of the sound, the thumbnuts 20 may be man- A ually turned to adjust the position of thereflector 11 with respect to the Yreflector portions 10 and 8 and theoutlet of the tube 1.

While I have herein described and upon the drawings shown a preferredembodiment of the invention, it is to be understood that it is notlimited to the particular details, arrangement of parts andconstructions described aiid shown, but that other details, arrangementsof parts and constructions are comprehended by the invention withoutdeparting from the spirit thereof.

Having thus described my invention, I claim: 1. A sound amplifiercomprising a horn member formed with a central passage, a flaringannular wall extending rearwardly from the forward end of said passage,a flaring reflector opposite the forward end of said central passage andspaced from the same and the wall to provide a reflex passagetherebetween for the sound leaving the forward end of the centralpassage, a threaded block in the central passage and formefl withapertures having stream-line surfaces to provide minimum obstruction tothe passage of sound waves, a threaded adjusting member carried by thereflector and threadedly engaging said block to provide for theadjustment of said reflector relative to said horn member.

2. A sound amplifier comprising a sound transmitting passage, soundreflecting m'eans at one cnd of the passage, a supporting member withinthe passage, a supporting element secured to said reflecting means andconnected to said member for supporting the reflecting means in givenrelation to said passage.

3. A sound amplifier comprising a sound transmitting passage, a soundreflecting means atan end of said passage, a supporting member withinsaid passage, a supporting element secured to said reflecting means andadjustahly connected to said member whereby the relation of saidreflecting means and said passage may be varied as desired.

4. A sound amplifier comprising a sound transmitting passage having aflared outlet end, a sound reflecting member having a tapered centralpart extending into said flared outlet en`d, and means for rotatablysupporting said reflecting member whereby it may be adjusted withrelation to said outlet end. l 5. A sound amplifier comprising a. soundtransmitting passage havin a sound outlet end, a sound reflect-in memker opposite said end, means associate with said passage and said memberfor rotatably supporting said member, said means being adapted when saidmember is rotated to permit relative adjustment of said passage and saidmember. j

6. A'sound amplifier comprising a horn member formed with a centralpassage, a flaring annular wall extending rearwardly from the forwardend of said assage, a flaring sound guide opposite the orward end ofsaid central passage. and spaced from the same and the wall to provide asound assage therebetween for the sound leaving e forlao ward end of thecentral passage, a threaded block in the central passage and formed withapertures having stream-line surfaces t`o provide minimum obstruction tothe passage of sound waves, a threaded adjustin member carried by theguide and threade ly engaging said block to provide for the adjustmentof said guide relative to said horn member.

7. A sound am lilier having a tubular portion forming a aring soundconveying passage, a supporting element in said tubulaiportion, saidtubular portion having an extension bent backwardly and outwardly, asound directing member disposed opposite the mouth of said tubularportion and arranged to direct the sound waves backwardly along saidextension, and means secured to said directing member and adjustablyconnected to said element for adjusting the relation of said directingmember with relation to said tubular portion and said extension.

8. A sound amplifier comprising a central tubular portion open at theforward end thereof, a sound directing member opposite said open end andhaving a rearwardly extending portion, the forward end of the tubularportion continuing rearwardly and being spaced from the rearwardlyextending portlon of the sound directing member to provide a soundpassage therebetween, a spider in said tubular portion, and meanscarried by said sound directing member and adjustably connected to said,spider.

9. A sound amplifier comprising a central `tubular portion open at theforward end thereof, a sound directing member opposite said open end andhaving a rearwardly extending portion, the forward end of the tubularportion continuing rearwardly and beinggspaced from the rearwardlyextending portion of the central tubular portion to provide a compactlyarranged horn wall, and

a sound directing means for receiving and directing the sound emittedfrom said tubular portion, an element secured within said tubularportion, anda member secured to said sound directing member andadjustably connected to said element for adjustmg said latter member.

10. A sound amplifier comprising a central hollow conical member, anouter hollow frusto-conical member, and an intermediate hollowfrusto-conical member having its smaller end connected to the larger endof the central member and the larger end connected to the smaller end ofthe outer member and a sound directing means opposite to and beyond thelarger end of the central member and extending toward and terminatingnear to the smaller end of the outer member and being spaced therefromto form a passage therebetween, and means for adjustably mounting saidsound directing means for varying the space between said 'means and theintermediate member.

11. A sound amplifier comprising a central hollow conical member, anouter hollow frusto-conical member, and an intermediate hollowfrusto-conical member havin its smaller end connected to the larger enof the central member and its larger end connected to the smaller end ofthe outer member and a reflector opposite to and beyond the larger endof the central member and extending toward and terminating near to thesmaller end of the outer member and being spaced therefrom to form apassage therebetween, a supporting element carried by said outer member,and means thereon for adjustably holding the reflector opposite to andin spaced relation with the larger end of the central member. y

In witness whereof, I hereunto subscribe my name to this specification.

JESSE B. HAWLEY.

